Platform/Socionext/DeveloperBox: add SMBIOS type 17 table

This commit adds the SMBIOS type 17 table support for Developerbox.
The SPD can be accessed only from the SCP through I2C bus,
so this commit expects that SCP-firmware reads the SPD and
stores it in the non-secure SRAM.

This commit also reduces the edk2 stack size to allocate
the space for storing SPD. It requires 2KB, 512bytes * 4 DIMMs.

Cc: Leif Lindholm <leif@nuviainc.com>
Cc: Masami Hiramatsu <masami.hiramatsu@linaro.org>
Signed-off-by: Masahisa Kojima <masahisa.kojima@linaro.org>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>